The idea of living on a cruise ship might have long been a pipe dream for many people, but it’s slowly becoming a reality for a few. Four Seasons Ocean Residences is a 42,500 ship with $2.5 to $15 million residences (depending on whole or part ownership), expected to be ready by 2008. This news has been followed by the announcement of The Magellan from Residential Cruise Line Ltd., a $650 million project, where condos are a snip (*cough*) at $1.8 to $8 million. Construction of the latter won’t begin until 60% of the units have been sold.